1. Field of the Invention
The present invention relates to plasma display panels, and more particularly, to plasma display panels that can be easily manufactured and that have high bright room contrast ratios.
2. Description of the Related Art
Plasma display panels have recently drawn attention as replacements for conventional cathode ray tube display devices. Plasma display panels are apparatuses that display images using visible light emitted through a process of exciting phosphor materials patterned with ultraviolet rays generated from the discharge of a discharge gas filled between two substrates on which a plurality of electrodes are formed.
FIG. 1 is a partially cutaway exploded perspective view of a conventional alternating current (AC) type plasma display panel (PDP) 10. Referring to FIG. 1, the PDP 10 includes an upper plate 50 where images are displayed and a lower plate 60 parallel to the upper plate 50. A sustain electrode pair 12, including an X electrode 31 and a Y electrode 32, is disposed on a front substrate 11 of the upper plate 50, and address electrodes 22, which are positioned perpendicular to the X electrode 31 and the Y electrode 32, are disposed on a rear substrate 21 of the lower plate 60 facing a surface of the front substrate 11 on which the sustain electrode pair 12 is disposed. A front dielectric layer 15 covering the sustain electrode pair 12 is formed on a rear surface of the front substrate 11, and a rear dielectric layer 25 covering the address electrodes 22 is formed on a front surface of the rear substrate 21. A protective layer 16 (usually formed of MgO) is formed on a rear surface of the front dielectric layer 15, and barrier ribs 30 (which maintain a discharge distance and prevent electrical and optical cross-talk between discharge cells) are formed on the entire surface of the rear dielectric layer 25. A phosphor layer 26 (including red, green and blue phosphor layers) is coated on both side walls of the barrier ribs 30 and on the surface of the rear dielectric layer 25 where the barrier ribs 30 are not formed.
The X electrode 31 and the Y electrode 32 include transparent electrodes 31a and 32a respectively, and bus electrodes 31b and 32b respectively. The space formed by the sustain electrode pair (i.e., the X electrode 31 and the Y electrode 32), and the address electrodes 22 is a discharge cell 70 and is one discharge unit. The transparent electrodes 31a and 32a are formed of a transparent material, such as indium tin oxide (ITO), that does not block the progress of light emitted from the phosphor material 26 (which is a conductive material) toward the front substrate 11. However, transparent materials such as ITO generally have high resistance. Accordingly, if the sustain electrode pair 12 is formed using only the transparent electrodes 31a and 32a, a large voltage drop occurs in the direction of the sustain electrode pair 12. Therefore, the consumption of driving power is high and response speed is low. To address these problems, bus electrodes 31b and 32b formed of a metal with a narrow line width are disposed on the transparent electrodes 31a and 32a. 
However, in the X electrode 31 and the Y electrode 32 (which include the transparent electrodes 31a and 32a and the bus electrodes 31b and 32b), the transparent electrodes 31a and 32a are expensive and processes for manufacturing each of the transparent electrodes 31a and 32a and the bus electrodes 31b and 32b are required, thereby increasing manufacturing costs.
Also, the above PDP 10 has a low bright room contrast ratio due to very high reflective brightness.